Integrated circuit for controlling radio transmission of ack/nack information

ABSTRACT

A radio receiver apparatus that can effectively utilize GI to improve the reception quality. In this apparatus, a data extracting part extracts a data portion of a direct wave from a signal subjected to a radio reception process by a received RF part. A GI extracting part extracts, from the signal subjected to the radio reception process by the received RF part, GI having a length determined by an extracted GI length deciding part. The extracted GI is adjusted by a data position adjusting part such that its rear end coincides with the read end of the extracted data portion. A combining part combines the extracted data portion with the GI the data position of which has been adjusted. The combined signal is then supplied to a frequency axis equalizing part, which equalizes the signal distortions of the combined signal on the frequency axis.

BACKGROUND

1. Technical Field

The present invention relates to a radio receiving apparatus and a radiotransmitting apparatus. More particularly, the present invention relatesto a radio receiving apparatus and a radio transmitting apparatus usinga single-carrier transmission system.

2. Description of the Related Art

In recent years, frequency equalization single-carrier transmissionsystems have been studied with an eye toward next-generation mobilecommunication systems. In the frequency equalization single-carriertransmission system, data symbols arranged in the time domain aretransmitted by a single carrier. A receiving apparatus corrects signaldistortion in the transmission path by equalizing that distortion on thefrequency axis. More specifically, the receiving apparatus calculates achannel estimation value for each frequency on the frequency domain, andperforms weighting for equalizing channel distortion on afrequency-by-frequency basis. Then the received data is demodulated.

The art disclosed in Patent Document 1 relates to the above frequencyequalization single-carrier transmission systems. This art will bebriefly described below. As shown in FIG. 1, the transmission systemdisclosed in Patent Document 1 generates signals in which apredetermined portion of the rear part of transmission data (data partin the drawing) is attached to the head of the data part as a guardinterval (hereinafter abbreviated as “GI”). The signals generated arethen transmitted from the transmitting apparatus, and signals combiningdirect waves and delayed waves arrive at the receiving apparatus. At thereceiving apparatus, as shown in FIG. 2, a timing synchronizationprocess is performed for the received data, and signals of the length ofthe data part are extracted from the beginning of the data part of thedirect wave. The extracted signals thereby include the direct wavecomponent, the delayed wave component and the noise component from thereceiving apparatus, and the extracted signals combine all of thesecomponents. Then, the extracted signals are subjected to signaldistortion correction process in the frequency domain (frequency domainequalization) and demodulated.

A GI is also called a cyclic prefix (“CP”).

Patent Document 1: Japanese Patent Application Laid-Open No. 2004-349889

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention

However, according to the art disclosed in Patent Document 1, insertingGIs equals transmitting the same data repeatedly, and so the energy ofGI parts not used in decoding is wasted. Generally, GIs are made 10 to25% of the data length. In other words, nearly 10 to 25% of transmissionenergy is always wasted.

It is therefore an object of the present invention to provide a radioreceiving apparatus and a radio transmitting apparatus that improvereceived quality through effective use of GI.

Means for Solving the Problem

The radio receiving apparatus of the present invention employs aconfiguration including: a receiving section that receives a signal inwhich a cyclic prefix is added to a data part; an extracting sectionthat extracts the cyclic prefix of the signal received by the receivingsection; and a combining section that combines the data part of thesignal received by the receiving section and the cyclic prefix extractedby the extracting section.

The radio transmitting apparatus of the present invention employs aconfiguration including: a mapping section that maps first data to apart occupying a cyclic prefix length or shorter from an end of a datapart, and second data, which is different from the first data, to a partother than the part where the first data is mapped; an adding sectionthat generates a cyclic prefix having the cyclic prefix length from thedata part after the mapping and adds the gene rated cyclic prefix to theend of the data part; and a transmitting section that transmits the datain which the cyclic prefix is added to the data part.

Advantageous Effect of the Invention

According to the present invention, received quality is improved througheffective use of cyclic prefixes.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 shows a method of generating GIs;

FIG. 2 explains receiving processing in the receiving apparatusdisclosed in Patent Document 1;

FIG. 3 is a block diagram showing a configuration of the receivingapparatus, according to Embodiment 1 of the present invention;

FIG. 4 shows data received by the receiving apparatus shown in FIG. 3;

FIG. 5 explains receiving processing in the receiving apparatus shown inFIG. 3;

FIG. 6 is a block diagram showing a configuration of the transmittingapparatus, according to Embodiment 2 of the present invention;

FIG. 7 explains a method of generating GI;

FIG. 8 is a transmission format showing a method of data mapping;

FIG. 9 is a transmission format showing a method of data mapping;

FIG. 10 is a transmission format showing a method of data mapping;

FIG. 11 is a transmission format showing a method of data mapping;

FIG. 12 is a transmission format showing a method of data mapping;

FIG. 13 is a block diagram showing a configuration of the receivingapparatus, according to Embodiment 4 of the present invention;

FIG. 14 explains receiving processing in a receiving apparatus shown inFIG. 3;

FIG. 15 is a block diagram showing a configuration of a transmittingapparatus, according to Embodiment 4 of the present invention;

FIG. 16 is a transmission format showing a method of data mapping;

FIG. 17 is a transmission format showing a method of data mapping;

FIG. 18 explains a transmission process, according to Embodiment 5 ofthe present invention;

FIG. 19 is a transmission format showing a method of data mapping;

FIG. 20 is a transmission format showing a method of data mapping;

FIG. 21 is a transmission format showing a method of data mapping;

FIG. 22 is a transmission format showing a method of data mapping;

FIG. 23 is a transmission format showing a method of data mapping; and

FIG. 24 is a transmission format showing a method of data mapping.

DETAILED DESCRIPTION

Embodiments of the present invention will be described below in detailwith reference to the accompanying drawings.

Embodiment 1

FIG. 3 is a block diagram showing a configuration of receiving apparatus100 according to Embodiment 1 of the present invention. In the figure,RF receiving section 102 performs predetermined radio receivingprocessing such as down-conversion and ND conversion for a signalreceived via antenna 101, and outputs the processed signal to directwave timing detecting section 103, data extracting section 104, maximumdelay time detecting section 105 and GI extracting section 107.

Direct wave timing detecting section 103 detects the timing of thebeginning of the data part of the direct wave (the direct wave timing)from the signal outputted from RF receiving section 102 as shown in FIG.4, and outputs the detected timing to data extracting section 104 and GIextracting section 107.

Based on the timing outputted from direct wave timing detecting section103, data extracting section 104 extracts the signal having a length ofT_(DATA) from the beginning of the data part of the direct wave of thesignal outputted from RF receiving section 102, and outputs theextracted signal to combining section 109.

Maximum delay time detecting section 105 detects the maximum time of thedelayed wave (the maximum delay time τmax) from the signal outputtedfrom RF receiving section 102, and outputs the detected maximum delaytime τmax to extracted GI length determining section 106.

Extracted GI length determining section 106 obtains T_(GI), whichindicates the length of the GI in the received data, and outputs thelength given by subtracting the maximum delay time τmax from theobtained T_(GI), to GI extracting section 107 and data separatingsection 111.

GI extracting section 107 extracts the GI having the length given byextracted GI length determining section 106, and outputs the extractedGI (hereinafter referred to as “extracted GI”) to data positionadjusting section 108. Data position adjusting section 108 adjusts therear end of the extracted GI outputted from GI extracting section 107 tothe rear end of the data part, and outputs the extracted GI after thedata position adjustment, to combining section 109.

Combining section 109 combines the data part outputted from dataextracting section 104 and the extracted GI outputted from data positionadjusting section 108, and outputs the combined signal to frequencydomain equalization processing section 110. Frequency domainequalization processing section 110 corrects the distortion of thesignal outputted from combining section 109 by correcting the distortionof the signal in the frequency domain, and outputs the corrected signalto data separating section 111.

Data separating section 111 separates the signal outputted fromfrequency domain equalization processing section 110 at the positiongoing back the length of the extracted GI determined at the extracted GIlength determining section 106 from the rear end of the data part. Thatis, data separating section 111 separates the part of the data partcombined with the extracted GI. The part including the beginning of thedata part, not combined with the extracted GI, is outputted todemodulating section 112. The part including the rear end of the datapart, combined with the extracted GI, is outputted to demodulatingsection 113.

Demodulating sections 112 and 113 each demodulate the data outputtedfrom data separating section 111. Demodulating section 112 outputsdemodulated data

A and demodulating section 113 outputs demodulated data B.

Next, the operations of receiving apparatus 100 having the aboveconfigurations will be explained with reference to FIG. 5. Dataextracting section 104 extracts a portion occupying data part lengthT_(DATA) from the beginning of the data part, from the received signalcombining the direct wave component, the delayed wave component and thenoise component in the receiving apparatus (hereinafter simply “noisecomponent”).

In addition, GI extracting section 107 extracts the GI part subtractingthe maximum delay time τmax from the GI length T_(GI). To be morespecific, GI extracting section 107 extracts the part of the GI goingback the length of the maximum delay time τmax from the beginning of thedata part (rear end of the GI), that is, the part of the GI that is notinterfered with the data of adjacent time.

Data position adjusting section 108 adjusts the data position of theextracted GI such that the rear end of the extracted GI and the rear endof the extracted data part match. Combining section 109 combines theextracted GI after the data position adjustment with the data part. Thisextracted GI and the rear end of the extracted data part extracted bydata extracting section 104 are the same signal. To be more specific,the parts subjected to the combining have different noise components,and so combining these parts results in improved SNR (Signal to NoiseRatio) in the combined part. The signal combined in combining section109 is subjected to signal distortion equalization in frequency domainequalization section 110. The SNR improves in the part combined with theextracted GI, so that error rate characteristics also improve.

According to Embodiment 1, demodulation can be performed througheffective use of the energy of GIs, by extracting from the GI includedin received data the part that is not interfered with the data ofadjacent time and by combining the extracted GI with the rear end partof the data part. Consequently, according to Embodiment 1, the SNR ofthe combined part improves, so that errors decrease in the combinedpart.

Embodiment 2

In the case of multicarrier transmission such as the OFDM scheme, bycombining GI parts, the SNR improves in part of the OFDM symbol in thetime domain. However, when an OFDM symbol is converted from the timedomain to the frequency domain, SNR improvement is distributed over allsubcarriers constituting the OFDM symbol. As a result, although the SNRof each symbol that is mapped to the subcarriers improves equally, thedegree of improvement is small.

On the other hand, in single carrier transmission like the presentinvention, symbols allocated in the time domain are transmitted bysingle carriers, so that, by combining GI parts, the SNR improves onlyin the symbols of GIs. Further, the SNR is expected to improve as muchas about 3 dB.

With multicarrier transmission, the SNR of each symbol can be improvedequally at low levels. On the other hand, in single carrier transmissionlike the present invention, the SNR can be improved in high levels onlyin part of the symbols deriving GIs.

The present embodiment will focus on such characteristics of GI parts insingle carrier transmissions.

FIG. 6 is a block diagram showing a configuration of transmittingapparatus 200, according to Embodiment 2 of the present invention.According to the figure, RF receiving section 202 performs predeterminedradio receiving processing such as down-conversion and A/D conversionfor a signal received via an antenna 201, and outputs the processedsignal to τmax information obtaining section 203.

τmax information obtaining section 203 obtains τmax informationindicating the maximum time of the delayed wave (the maximum delaytime), and outputs the obtained τmax information to data mappingdetermining section 204.

Based on τmax information outputted from τmax information obtainingsection 203, data mapping determining section 204 determines the datamapping method and reports the determined data mapping method to datamapping section 207. The data mapping method will be described later.

On the other hand, transmission data is separated into data A and B, anddata A is inputted to modulating section 205 and data B is inputted tomodulating section 206.

Modulating sections 205 and 206 each modulate the inputted data usingmodulation schemes such as PSK modulation or QAM modulation and outputthe modulated signal to data mapping section 207.

Data mapping section 207 maps the signals inputted from modulatingsections 205 and 206 by the data mapping method determined by datamapping determining section 204, and outputs the mapped signal to GIadding section 208.

GI adding section 208 generates a GI by copying a predetermined portionfrom the rear end of the data part of the signal outputted from datamapping section 207, and outputs the signal in which the generated GI isattached to the beginning of the data part, to RF transmitting section209. FIG. 7 shows a specific example of the method of generating GIs.According to the specific example shown in FIG. 7, the data part lengthis 16 symbols, and the GI length is 4 symbols. The symbols allocated inorder from the beginning of the data part are distinguished as symbolnumber 1 to 16. Four symbols of a GI length from the rear end of thedata part, that is, symbol number 13 to 16, are copied to generate a GI.

RF transmitting section 209 performs predetermined radio transmittingprocessing such as D/A conversion and up-conversion with the signaloutputted from GI adding section 208, and transmits the processed signalvia antenna 201.

Here, the data mapping method in data mapping determining section 204 isexplained. Data mapping determining section 204 obtains τmax informationtransmitted (fed back) from communicating parties. As shown in FIG. 8,data mapping determining section 204 maps significant information suchas the control channel, systematic bits, retransmission bits, ACK/NACKinformation (ACK or NACK), CQI (Channel Quality Indicator), TFCI(Transport Format Combination Indicator), information required fordecoding, pilot bits and power control bits, to the part occupyingT_(GI)-τmax from the rear end of the data part, that is, the part whereerror rate characteristics improve in receiving apparatus 100 ofEmbodiment 1. According to this mapping method, significant informationis correctly transmitted.

If transmitting apparatus 200 regards data A to be inputted tomodulating section 205 as significant information and data B to beinputted to modulating section 206 as standard information other thansignificant information, data mapping section 207 maps data A to thepart occupying T_(GI)-τmax from the rear end of the data part, and dataB to the rest of the data part.

According to Embodiment 2, significant information can be transmitted tothe receiving apparatus correctly, by finding the part where error ratecharacteristics improve based on τmax information and mapping thesignificant information to the part found out, so that overall systemthroughput improves.

Further, although a case has been described with the present embodimentwhere the FDD scheme is adopted and where τmax information is fed backfrom communication parties, the present invention is not limited tothis, and it is equally possible to adopt the TDD scheme. If the presentinvention adopts the TDD scheme, it will be possible to measure τmaxbased on received signals. FDD and TDD do not limit the method ofobtaining τmax.

Embodiment 3

In Embodiment 2, a data mapping method of performing data mapping basedon τmax information has been described. Now, other data mapping methodswill be described below. The data mapping method explained in Embodiment2 is method A, and the methods B to E, which are different methods frommethod A, will be described below.

First, as shown in FIG. 9, method B maps significant information to thepart occupying the GI length (T_(GI)) from the rear end of the datapart. According to this method B, due to variations of τmax, not allsignificant information that is mapped will have improved error ratecharacteristics. Still, according to this method B, when τmaxinformation is difficult to obtain or when installation of additionalcircuitry for obtaining τmax information is undesirable, error ratecharacteristics of significant information are more likely to improve.

Next, as shown in FIG. 10, method C maps significant information, in thepart occupying the GI length (T_(GI)) from the rear end of the datapart, in descending order of significance from the rear end of the datapart, because error rate characteristics are likely to improve nearerthe rear end of the data part.

The reason will be explained below. τmax can vary between zero andT_(GI). If τmax is zero, the error rate improves in the whole of thepart occupying T_(GI) from the rear end of the data part. Meanwhile,when τmax is T_(GI), the error rate in the whole of the part occupyingT_(GI) from the rear end of the data part is the same error rate as therest of the data part, error rate characteristics are not likely toimprove.

In actual systems, τmax is between zero and T_(GI), as shown in FIG. 8,and so, as τmax becomes smaller, there are more symbols, from the rearend of the data part, where error rate characteristics improve.Consequently, error rate characteristics are more likely to improve nearthe end of the data part and are less likely to improve far from therear end of the data part.

Due to these reasons, according to method C, as information becomessignificant, error rate characteristics are likely to improve.

Next, as shown in FIG. 11, method D determines the significance of dataand maps data from the rear end of the data part over the entirety ofthe data part in descending order of significance. According to methodD, mapping process over the entirety of the data part can be performedwith ease.

Next, as shown in FIG. 12, method E maps significant information to thepart occupying the GI length (T_(GI)) from the rear end of the data part(that is, where the GI originates from) excluding the symbols on bothends. In other words, method E maps significant information to a centerportion of the part deriving the GI with priority and does not mapinformation to both ends of that part. The reason is as follows.

In actual systems, the direct wave timing detected on the receivingapparatus side may be detected a little forward or backward with respectto the correct direct wave timing. In the case, in both ends of a GI,interference with the adjacent symbols occurs. That is, in actualsystems, the SNR is less likely to improve in a little range at bothends of the part deriving the GI.

For this reason, according to method E, with more significantinformation, error rate characteristics are more likely to improve.

Further, according to method E, τmax information is not necessary, sothat a τmax information obtaining section needs not be provided in thetransmitting apparatus. The same applies to methods B to D.

Embodiment 4

FIG. 13 is a block diagram showing a configuration of receivingapparatus 300, according to Embodiment 4 of the present invention.According to FIG. 13, the same components as those described in FIG. 3will be assigned the same reference numerals and their detaileddescriptions will be omitted. FIG. 13 is different from FIG. 3 in addingdemodulating section 303, in changing GI extracting section 107 to GIextracting section 301 and data separating section 111 to dataseparating section 302, and in removing maximum delay time detectingsection 105 and extracted GI length determining section 106.

GI extracting section 301 obtains T_(GI) which indicates the length ofthe GI in received data, and extracts the entire GI (the whole from thebeginning to the rear end of the GI) from the direct wave of the signaloutputted from RF receiving section 102, based on the obtained T_(GI)and the timing outputted from direct wave timing detecting section 103.The extracted GI is outputted to data position adjusting section 108.

Data separating section 302 separates the signal outputted fromfrequency domain equalization processing section 110 at the positiongoing back T_(GI) from the rear end of the data part and at the positiongoing back two T_(GI)'s from the rear end of the data part. The partincluding the beginning of the data part, not combined with theextracted GI, is outputted to demodulating section 112. The partincluding the rear end of the data part, combined with the extracted GI,is outputted to demodulating section 113. The part between the positiongoing back T_(GI) from the rear end of the data part and the positiongoing back two T_(GI)'s from the rear end of the data part is outputtedto demodulating section 303.

Demodulating section 303 demodulates the data outputted from dataseparating section 302 and outputs data C.

Next, the operations of receiving apparatus 300 having the aboveconfiguration will be explained with reference to FIG. 14. Dataextracting section 104 extracts data occupying the data part lengthT_(DATA) from the beginning of the data part of the direct wave, fromthe received signal combining the direct wave component, the delayedwave component and the noise component in the receiving apparatus. Inaddition, GI extracting section 301 extracts the GI of the direct wave.The extracted GI includes the GI of the direct wave, a portion of the GIof the delayed wave (T_(GI)-τmax), interference by the previous symbol(τmax) and the noise component.

Data position adjusting section 108 adjusts the data position of theextracted GI such that the rear end of the extracted GI and the rear endof the data part match. Combining section 109 combines the extracted GIafter the data position adjustment with the data part.

The combined signal, combined as such, is the signal combining allenergy of the GI of the direct wave, so that the SNR improves in thepart where the extracted GI is combined. On the other hand, the partimmediately preceding the part combined with the extracted GI includesinterference from the previous symbol, and so the SNR of the immediatelypreceding part degrades. Here, the average SNR over the entirety fromthe beginning to the rear end of the data part improves reliably and soerror rate characteristics improve.

FIG. 15 is a block diagram showing a configuration of transmittingapparatus 400, according to Embodiment 4 of the present invention.Further, according to FIG. 15, the same components as those described inFIG. 6 are assigned the same reference numerals and the details will beomitted. In comparison to FIG. 6, FIG. 15 adds modulating section 401,changes data mapping determining section 204 to 402, and removes RFreceiving section 202 and τmax information obtaining section 203.

Modulating section 401 modulates inputted data C using modulationschemes such as PSK modulation and QAM modulation and outputs themodulated signal to data mapping section 207.

Data mapping determining section 402 determines the data mapping methodand reports the determining data mapping method to data mapping section207. Here, the data mapping method reported to data mapping section 207will be explained using FIG. 16. The data mapping method, as shown inFIG. 16, maps significant information such as control channels,information required for decoding, systematic bits, pilot bits and powercontrol bits and ACK/NACK information (ACK or NACK), to the partoccupying T_(GI) length from the rear end of the data part, that is, thepart where error rate characteristics improve. Further, the data mappingmethod maps insignificant information such as parity bits and repeatingbits to the part between the position going back T_(GI) from the rearend of the data part and the position going back two T_(GI)'s from therear end of the data part, that is, the part where error bitcharacteristics degrade. According to this method, significantinformation is transmitted correctly to the receiving apparatus and thetransmission format can be utilized effectively by mapping insignificantinformation to the part where quality degrades.

Consequently, with transmitting apparatus 400, data A inputted tomodulating section 205 is significant information, data C inputted tomodulating section 401 is insignificant information, and data B inputtedto modulating section 206 is the other, standard information. In otherwords, data mapping section 207 maps data A to the part occupying T_(GI)from the rear end of the data part, data C to the part between theposition going back T_(GI) from the rear end of the data part and theposition going back two T_(GI)'s from the rear end of the data part, anddata B to the rest of the data part (before or at the position goingback two T_(GI)'s from the rear end of the data part).

In addition, data mapping determining section 402 may also use themethod shown in FIG. 17 in addition to the data mapping method describedabove. This method determines the significance of data and maps data indescending order of significance, from the part of good error ratecharacteristics. According to this method, information of greatsignificance is transmitted reliably to the receiving apparatus.

According to Embodiment 4, the GI of the direct wave included in thereceived signal is extracted and the part of the extracted GI iscombined with the rear end part of the data part before frequency domainequalization processing is performed, so that demodulation is performedthrough effective use of energy of the GI. As a result, the SNR improvesin the combined part.

Embodiment 5

Cases have been described above with Embodiments 1 to 4 where apredetermined portion of the rear part of the data part is attached tothe beginning of the data part as a GI. In contrast, according toEmbodiment 5 of the present invention, a predetermined portion of thefront part of the data part is attached to the rear end of the data partas a GI. Further, the components of the receiving apparatus according toEmbodiment 5 of the present invention are the same as shown in FIG. 3according to Embodiment 1, and this embodiment will be explained withreference to FIG. 3.

In FIG. 18, the receiving process according to the present embodiment isshown in a schematic manner. Data extracting section 104 extracts thepart occupying data part length T_(DATA) from the beginning of the datapart of the direct wave, from the received signal combined with thedirect wave component, the delayed wave component and the noisecomponent in the receiving apparatus.

Further, GI extracting section 107 extracts the GI part going backT_(GI)-τmax from the rear end of the part of the GI of the direct wave.That is, GI extracting section 107 extracts the proportion of the GIthat is not interfered with data of adjacent time.

Data position adjusting section 108 adjusts the position of theextracted GI such that the beginning of the extracted GI and thebeginning of the extracted data part match. Combining section 109combines the extracted GI after the data position adjustment with thedata part.

Next, data mapping methods E to H according to the present embodimentwill be explained. Further, the same transmitting apparatus componentsaccording to Embodiment 5 of the present invention are shown in FIG. 6in Embodiment 2, and the details are omitted.

First, as shown in FIG. 19, method E, which corresponds to method Ashown in FIG. 8, maps significant information to the part occupyingT_(GI)-τmax from the beginning of the data part, that is, to the partwhere error rate characteristics improve.

As shown in FIG. 20, method F, which corresponds to method B in FIG. 9,maps significant information to the part occupying the GI length(T_(GI)) from the beginning of the data part.

As shown in FIG. 21, method G, which corresponds to method C in FIG. 10,maps significant information in descending order of significance, fromthe beginning of the data, to the part occupying the GI length (T_(GI))from the beginning of the data part.

As shown in FIG. 22, method H, which corresponds to method D in FIG. 11,determines the significance of data, and maps data from the beginning ofthe data part, over the whole of the data part, in descending order ofsignificance.

According to Embodiment 5, when a portion of the front part of the datapart is added to the rear end of the data part as a GI, the energy ofthe GI can be utilized effectively for demodulation, so that the SNR ofthe combined part improves, thereby decreasing errors in the combinedpart. Further, significant information can be correctly transmitted tothe receiving apparatus, so that overall system throughput improves.

Embodiment 6

A case has been described above with Embodiment 5 where a predeterminedportion of the front part of the data part is added to the rear end ofthe data part as a GI and a portion of the GI is combined with the datapart. On the other hand, a case will be described here with thisEmbodiment 6 where a predetermined portion of the front part of the datapart is added to the rear end of the data part as a GI and the whole ofthe GI (from the beginning to the rear end of the GI) is combined withthe data part, employing mapping method I and J. Further, the sametransmitting apparatus components according to Embodiment 6 of thepresent invention are shown in FIG. 15 in Embodiment 4, and the detailsare omitted.

As shown in FIG. 23, method I corresponds to the method shown in FIG.16. Method I maps significant information to the part occupying T_(GI)from the beginning of the data part, maps insignificant information tothe part between the position going back T_(GI) from the beginning ofthe data part and the position going back two T_(GI)'s from thebeginning of the data part, and maps standard information to the rest ofthe data part (at or after the position two T_(GI)'s after the beginningof the data part).

As shown in FIG. 24, method J, which corresponds to the method shown inFIG. 17, determines significance of data and maps data from the partwhere is most preferable error rate characteristics, in descending orderof significance.

According to Embodiment 6, when a predetermined portion of the frontpart of the data part is added to the rear end of the data part as a GIand the GI and the data part are combined, significant information canbe transmitted correctly to the receiving apparatus. Thus, overallsystem throughput improves.

Further, “standard information” according to the above embodimentsincludes, for example, data channels such as HS-DSCH, DSCH, DPDCH, DCH,S-CCPCH and FACH in 3GPP standards.

Furthermore, “significant information” according to the aboveembodiments includes, for example in 3GPP standards, HS-SCCH associatedwith HS-DSCH, DCCH, S-CCPCH, P-CCPCH, and PCH for reporting controlinformation for HS-DPCCH and RRM (Radio Resource Management), and, DPCCHfor controlling a BCH physical channel.

In addition, “significant information” according to the aboveembodiments includes TFCI. TFCI is information for reporting dataformats, and so, if TFCI is received incorrectly, the data of the wholeframe or all subcarriers will be received incorrectly. Accordingly, itis effective to process TFCI as significant information in the aboveembodiments and improve error rate characteristics of TFCI.

Further, if control channels are roughly classified into the commoncontrol channel and the dedicated control channel, the common controlchannel may be processed as significant information in the aboveembodiments and the dedicated control channel may be processed asstandard information in the above embodiments. The common controlchannel is commonly transmitted to a plurality of mobile stations and sorequires better error rate characteristics than the dedicated controlchannel that is transmitted individually to each mobile station.

Further, the significant information in the above embodiments includesinitialization information (initialization vector) used in informationcompression or data encryption. This initialization vector provides abase for later communications, and so, if the initialization vector isreceived incorrectly, a series of communications later may be not bepossible at all. Accordingly, it is effective to process initializationvector as significant information in the above embodiments and improveerror rate characteristics of the initialization vector.

Further, significant information in the above embodiments may includedata of the center channel in multiplex transmission signals. Formultiplex transmission signals, errors with the data of the centerchannel have more degradative influence in audibility than errors withother channels (the right, left or rear channel).

For example, although with the above embodiments cases have beendescribed where the present invention is configured by hardware, thepresent invention may be implemented by software.

Each function block employed in the description of each of theaforementioned embodiments may typically be implemented as an LSIconstituted by an integrated circuit. These may be individual chips orpartially or totally contained on a single chip. “LSI” is adopted herebut this may also be referred to as “IC”, “system LSI”, “super LSI”, or“ultra LSI” depending on differing extents of integration.

Further, the method of circuit integration is not limited to LSI's, andimplementation using dedicated circuitry or general purpose processorsis also possible. After LSI manufacture, utilization of an FPGA (FieldProgrammable Gate Array) or a reconfigurable processor where connectionsand settings of circuit cells within an LSI can be reconfigured is alsopossible.

Further, if integrated circuit technology comes out to replace LSI's asa result of the advancement of semiconductor technology or a derivativeother technology, it is naturally also possible to carry out functionblock integration using this technology. Application of biotechnology isalso possible.

The present application is based on Japanese Patent Application No.2005-066813, filed on Mar. 10, 2005, Japanese Patent Application No.2005-212671, filed on Jul. 22, 2005, and Japanese Patent Application No.2006-063972, filed on Mar. 9, 2006, the entire contents of which areexpressly incorporated by reference herein.

INDUSTRIAL APPLICABILITY

The radio receiving apparatus and the radio transmitting apparatusaccording to the present invention carry out demodulation utilizing GIseffectively and improve received quality and may be applied to basestation apparatus and mobile station apparatus used in a frequencyequalization single-carrier transmission system.

1. An integrated circuit that controls transmission, in a single carriertransmission system, of a plurality of data symbols that are included ina data part and arranged between a front end and a rear end of the datapart, the integrated circuit comprising: an arrangement controlconfigured to command arrangement of the plurality of data symbols tomap at least one data symbol including ACK/NACK information from therear end of the data part; and a transmission control configured tocommand transmission, during a cyclic prefix period, of one or more datasymbols including data that is the same as data included in a portion ofthe plurality of data symbols, the portion ranging from the rear end ofthe data part and corresponding to the cyclic prefix period to therebycontain said at least one data symbol including ACK/NACK information,the transmission control being further configured to commandtransmission of the plurality of data symbols in the data part after thecyclic prefix period, to thereby command transmission, during the cyclicprefix period, of said one or more data symbols including data that isthe same as data included in the portion containing said at least onedata symbol including ACK/NACK information, and to command transmission,during transmission of the portion, of said at least one data symbolincluding ACK/NACK information, such that the ACK/NACK information istransmitted twice within a combination including a data part and acyclic prefix period that precedes the data part.
 2. The integratedcircuit of claim 1, wherein the cyclic prefix period comprises a guardinterval.
 3. The integrated circuit of claim 1, wherein the plurality ofdata symbols are OFDM data symbols.
 4. The integrated circuit of claim1, wherein the portion ranging from the rear end of the data part hasimproved error rate characteristics than the rest of the data part. 5.The integrated circuit of claim 1, wherein the arrangement control isfurther configured to map at least one data symbol including significantinformation other than the ACK/NACK information in said portion rangingfrom the rear end of the data part, such that said significantinformation is transmitted twice, both during the cyclic prefix periodand during transmission of said portion.
 6. The integrated circuit ofclaim 5, wherein the significant information is one or more of a controlchannel, systematic bits, retransmission bits, CQI (channel qualityindicator), TFCI (transport format combination indicator), informationrequired for decoding, pilot bits, and power control bits.
 7. Theintegrated circuit of claim 1, further comprising a modulation controlconfigured to command modulation of the plurality of data symbols.
 8. Anintegrated circuit that controls transmission, in a single carriertransmission system, of a plurality of data symbols that are included ina data part and arranged between a front end and a rear end of the datapart, the integrated circuit comprising: an arrangement moduleconfigured to control arrangement of the plurality of data symbols tomap at least one data symbol including ACK/NACK information from therear end of the data part; and a transmission module configured tocontrol transmission, during a cyclic prefix period, of one or more datasymbols including data that is the same as data included in a portion ofthe plurality of data symbols, the portion ranging from the rear end ofthe data part and corresponding to the cyclic prefix period to therebycontain said at least one data symbol including ACK/NACK information,the transmission control being further configured to commandtransmission of the plurality of data symbols in the data part after thecyclic prefix period, wherein the ACK/NACK information is transmittedtwice, both during the cyclic prefix period and during transmission ofthe portion ranging from the rear end of the data part.
 9. Theintegrated circuit of claim 8, wherein the cyclic prefix periodcomprises a guard interval.
 10. The integrated circuit of claim 8,wherein the plurality of data symbols are OFDM data symbols.
 11. Theintegrated circuit of claim 8, wherein the portion ranging from the rearend of the data part has improved error rate characteristics than therest of the data part.
 12. The integrated circuit of claim 8, whereinthe arrangement control is further configured to map at least one datasymbol including significant information other than the ACK/NACKinformation in said portion ranging from the rear end of the data part,such that said significant information is transmitted twice, both duringthe cyclic prefix period and during transmission of said portion. 13.The integrated circuit of claim 12, wherein the significant informationis one or more of a control channel, systematic bits, retransmissionbits, CQI (channel quality indicator), TFCI (transport formatcombination indicator), information required for decoding, pilot bits,and power control bits.
 14. The integrated circuit of claim 8, furthercomprising a modulation control configured to command modulation of theplurality of data symbols.